Progress and development trend of open-pit mining technology (including blasting technology) in metal mines in China

[1.8 Super large open pit safe and efficient mining technology] This topic is the national "Twelfth Five-Year" science and technology research topic, aiming at the characteristics of super large open pit iron ore deposits in China and China's overseas, from the perspective of high efficiency, economy and safety, It has developed a dynamic optimization technology for stripping flood peak control of steeply-tilted open pit deposits, a production scale optimization technology based on economic dynamic assessment and the balance of total mining and stripping, an adaptive technology for ore loss and dilution control under the interference of multiple factors in large open pit mining, and a new level multi-zone development technology for extra-large open pit mines, breaking through key technical difficulties in efficient and low-cost mining of large open pit mines. The technical and economic system of super large open-pit mining has been established, and the overall technology is at the international leading level.

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Comparison of open pit mining technology with foreign advanced level

China's metal mine open-pit mining technology has made remarkable achievements, in the open-pit mining steep slope mining, high step mining, penetration and explosion technology has developed rapidly and has certain technical advantages, basically follow the international research trend, and even some technologies have reached the international leader. However, in the open-pit mine transportation system, large-scale equipment, automation has been close to the international advanced level, in the digital mine, mining monitoring means modernization and modern mine management and other aspects of the gap is large.

[Continuous mining process, diversified transportation mode, efficient] In terms of steep slope mining, the slope Angle of China's steep slope mining is about 40°, and the working slope Angle of the United States, Canada and Russia with more advanced open-pit mining technology has reached about 45°. As in foreign countries, the discontinuous-continuous mining technology of most mines in China realizes the movable rock crushing and belt transportation in stope; The steep slope railway can extend the railway transportation to the deeper stage of the open pit mine, increase the transportation capacity by 25%, reduce the transportation cost by 20%, and China has realized the steep slope railway slope limit of 45‰ ~ 50‰. In terms of high level mining, China has realized 18m high level production in Nanfen Iron Mine, which reduces the unit mining cost; In terms of open-pit mining technology, most of our country has reached the international advanced level.

[Large-scale mining equipment] In terms of drilling RIGS, the perforating equipment of metal open-pit mines in China includes cone drill and submerged hole drill. Large mines mainly use cone drill with drilling diameters of 250mm and 310mm, while small and medium-sized open-pit mines mainly use submerged hole drilling with drilling diameters of 200mm. Foreign drilling equipment basically uses cone drill, drilling diameter is mostly 311 ~ 381mm, 445mm, 559mm. In terms of shovel loading, electric shovel equipment accounts for an absolute advantage in foreign countries (about 48%), but the application of hydraulic shovel is constantly expanding (about 26%), and the bucket capacity is mainly 21m3, 38m3, 43m3; At present, Taiyuan Heavy Industry has developed WK-75 mining electric shovel, bucket capacity of 75m3, for the world's largest level of excavator. In terms of automobile transportation, the electric wheel vehicles used in large foreign mines at present, their carrying mass is mostly 240 tons, 320 tons, 150 tons, and the maximum can reach 363 tons, and the mass of large open-pit mining vehicles in China is mostly 120 tons and 170 tons. In November 2015, Aerospace Heavy Industry independently developed H-ton 3363 two-axis electric wheel mining dump truck, carrying mass reached 363 tons, marking the domestic open-pit mining automotive equipment into the ranks of the world's advanced level.

[Blasting technology] Foreign open-pit mines widely use the large-area multi-row differential blasting technology to increase the amount of ore and rock in each blasting, reduce the number of blasting, improve the utilization rate of equipment, and improve the blasting quality, which is a general form. The advent of new explosives and blasting equipment has great influence on improving the blasting precision, improving the blasting quality and strengthening the blasting safety.

[Production management automation] Foreign metal open-pit mines have developed a number of software platforms in terms of production management automation, computer online control and design applications, such as Gemcom's surpac, mineshed, whi Ton ton le, Micromine's micromine, fieldmarshal, gbis, etc., have made remarkable achievements. These software platforms can optimize and design the surface mine boundary, prepare production schedule, plan the surface mine development strategic planning, production simulation analysis, evaluate and develop the transportation system and select the loading equipment, prepare the vehicle dispatching system, realize the maintenance plan management of mining and loading equipment, plan the storage and supply control of spare parts, simulate the main production process and optimize the working parameters. Conduct financial analysis, etc. In recent years, China has also independently developed related software platforms, such as dimine software independently developed by the Digital Mining Research Center of Central South University and 3DMINE software developed by Beijing 3Dmine Mining Software Company, but the overall degree of automation management is not high and needs to be further strengthened.